gdb/gcc.patch

   1 In the 2.3.2 release of gcc/g++, how the compiler handles resolving
   2 multiple inheritance lattices was reworked to properly discover
   3 ambiguities.  We recently found an example which causes this new
   4 algorithm to fail in a very subtle way.  For the time being, this
   5 patch will make the compiler use the old algorithm, which works for
   6 the failing case we've found.  Note it will revert the compiler's
   7 ability to properly deduce MI ambiguities in many cases (to its state
   8 in 2.2.2 and 2.3.1).  This bug will be fixed in the next gcc/g++
   9 release.
  10
  11 Brendan Kehoe (brendan@cygnus.com)
  12
  13 *** cp-search.c.~1~     Thu Feb 18 18:03:24 1993
  14 --- cp-search.c Thu Feb 18 18:03:27 1993
  15 ***************
  16 *** 2389,2392 ****
  17 --- 2389,2393 ----
  18         if ((*qfn)(base_binfo))
  19         {
  20 + #if 0
  21           if (fn == dfs_init_vbase_pointers)
  22             {
  23 ***************
  24 *** 2464,2467 ****
  25 --- 2465,2469 ----
  26               saw_first_vbase = save_saw_first_vbase;
  27             } else
  28 + #endif
  29               dfs_walk (base_binfo, fn, qfn);
  30         }
  31 *************** dfs_init_vbase_pointers (binfo)
  32 *** 2658,2661 ****
  33 --- 2660,2664 ----
  34       return;
  35
  36 + #if 0
  37     this_vbase_ptr = vbase_decl_ptr_intermediate;
  38
  39 *************** dfs_init_vbase_pointers (binfo)
  40 *** 2662,2668 ****
  41     if (TYPE_POINTER_TO (type) != TREE_TYPE (this_vbase_ptr))
  42       my_friendly_abort (125);
  43
  44 - #if 0
  45     distance = get_base_distance (type, TREE_TYPE (vbase_decl), 0, &path);
  46     if (distance == -2)
  47       {
  48 --- 2665,2672 ----
  49     if (TYPE_POINTER_TO (type) != TREE_TYPE (this_vbase_ptr))
  50       my_friendly_abort (125);
  51 + #endif
  52
  53     distance = get_base_distance (type, TREE_TYPE (vbase_decl), 0, &path);
  54 + #if 0
  55     if (distance == -2)
  56       {
  57 *************** dfs_init_vbase_pointers (binfo)
  58 *** 2669,2672 ****
  59 --- 2673,2677 ----
  60         error ("inheritance lattice too complex below");
  61       }
  62 + #endif
  63     while (path)
  64       {
  65 *************** dfs_init_vbase_pointers (binfo)
  66 *** 2682,2685 ****
  67 --- 2687,2691 ----
  68       this_vbase_ptr = convert_pointer_to (type, vbase_decl_ptr);
  69
  70 + #if 0
  71     /* This happens when it is ambiguous. */
  72     if (this_vbase_ptr == error_mark_node)